Tree bark samples

Multi-element analysis on 57 tree bark samples collected at different locations (near power plants, closed to a motorway, in urban or in uncontaminated rural areas) in the UK in order to study environmental contamination was performed by quadrupole based ICP-MS (Elan 6000, Perkin Elmer Sciex) after microwave induced digestions of samples and dilution. The measured concentration ranges of 52 elements varied from the sub-ngg-1 range (e.g., Hf or Pt) to the low % range (e.g. for Ca) and are summarized in Table 9.24.4 Oriental Tobacco Leaves SRM (CTA-OTL-1) was employed to validate the analytical ICP-QMS method. 

Table 9.24 Concentration range of elements in tree bark samples.

Although the development of trace analysis is considered to have begun with studies related to the determination of trace elements, from the pharmaceutical point of view, the beginning of this field of science should be sought in the analysis of dmgs and especially in the search for active compounds in different t3 pes of pharmaceutical decoctions, tinctures, and macerations. Isolation of opium and later morphine from poppy juice, or isolation of quinine from cinchona tree bark, were nothing other than preparation and concentration of a sample before performing trace analysis [1-3]. 

In addition to seeds, other plant parts as leaves, stems, bark, roots, bulbs, and tubers are tested The ELISA procedures used for the various products will be mainly the same. However, sample preparation varies widely among plant species and plant parts In the Netherlands, the Pollflhne press is the most popular tool to prepare extracts. Relatively dry plant parts such as the leaves of some fruit trees, bark material, roots, bulbs and tubers are extracted by adding buffer to the press just above the sample during grinding. 

It has been suggested that a suitable surrogate parameter for atmosphere/plant partition is the octanol/air partition coefficient (Harner and Mackay 1995). Direct measurements of this coefficient for a number of chlorinated aromatic hydrocarbons revealed, however, its sensitivity to temperature. The results of a study in which a number of PAHs were analyzed throughout the year in samples of tree bark, leaves, pine needles, and in the atmosphere also underscore the importance of temperature, since there was a cyclical partition between the atmosphere and the tree canopy (Simonich and Hites 1994). The contribution to the atmosphere through direct volatilization from the terrestrial environment was not resolved in this study. 

In the laboratory, remains of the tree bark and other lichen species where removed from P. sulcata transplants. Then each sample was put in a nylon sieve and rinsed in 18 Mfl water ejected for 30 s, freeze dried and ground in a Teflon (balls and capsule) mill. 

Tree deposits. Recovery of deposits from the components for fruit, foliage, and bark were estimated by exposure of 5 x 10 cm strips of teflon film placed in tree canopy to mimic tree surfaces. Two sets of four teflon films attached to. 95cm diameter wooden dowels were placed in the tops, and at shoulder height in the trees. The dowels were mounted 30.5cm into the canopy on the N, E, S, and W sides of the tree. This procedure was followed for two of the captan applications, one by air on 7/1/81, and the other by ground on 7/15/81. One tree was sampled in the center of the orchard for each application. 

Bark samples were collected from different parts of the tree. After air-drying, each sample was ground to pass a 40-60 mesh sieve and mixed homogeneously. Samples were prepared as follows ... 

Fig. 21.1 (a) Cumait plantation of Cinchtma tree in India (b) Workers sorting cinchona bark in Tjinjiroean (West Java, form the period 1915—1930, collection of Tropenmuseum of the Royal Tropical Institute (KIT), (c) cinchona bark samples, (d) authentic samples of cinchona alkaloids isolated by Pelletier and Caventou in 1834 roku (from www.sciencemuseum. org.uk)... 

Another study identifying enriched U in the ambient environment near a nuclear facility was reported by Beilis et al. [21]. They used digested samples of tree bark as reporters of particulate U released from the Tokai-Mura nuclear facility in Japan. A quadrupole-based ICP-MS system was used to measure U/ U ratios in the bark samples. Controls from locations at Yakushima and Tokyo exhibited naturally occurring U with U/ U = 0.00725, whereas samples from the Tokai-Mura vicinity exhibited U/ U values of up to 0.0145, signifying mixing between naturally occurring U and enriched U. 

Frankincense, also called olibanum, is a natural oleo gum resin that exudes from incisions in the bark of Boswellia trees [46, 47]. Diterpenes like incensole or isoincensole and their oxide or acetate derivatives (see Figure 10.3) are characteristic biomarkers of olibanum [48]. Although diterpenoid hydrocarbons possessing the cembrane skeleton have been isolated from a variety of terrestrial and marine organisms, their occurrence and particularly that of cembrenes A and C (see Figure 10.3) is supplementary proof of the presence of olibanum in a sample. Optimisation of the SPME conditions was done with the aim of trapping these low volatile diterpenes. 

The NCI scientists discovered that extracts of the bark and needles of a yew tree, Taxus brevifolia of the Pacific Northwest, killed trunor cells. Fresh samples were obtained from the forests in the state of Washington in August 1962. Paclitaxel was first isolated from yew tree extract in 1967, and retested on cells in the laboratory. After it was found to be effective in tests on animals with tmnors, paclitaxel was studied in a large munber of human cancer patients and finally approved by the Food and Drug Administration (FDA) in 1992 for use in treating cancer in people. 

Sampling of trees by removing bark or by condition of the tree and treating only those trees with active brood would conserve these valuable natural enemies. 

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